In the processing and packaging of semiconductor devices, in the interconnection of certain devices, flip chip and thermocompression bonding techniques are used. In connection with such techniques, a first substrate (e.g., a die) is bonded to a second substrate (e.g., a wafer, another die, another substrate such as a leadframe, etc). Generally, the first substrate is a semiconductor element. There are conductive structures/contacts (e.g., pillars, traces, etc.) on each of the first and the second substrate. For example, on the first substrate (e.g., a die) the conductive traces may be conductive structures, such as copper pillars with solder on an end portion of the pillars. During thermocompression bonding the solder is melted, and then re-solidified, thereby bonding the conductive structures/contacts on the first substrate to those on the second substrate.
In conventional thermocompression bonding, the substrate to which a semiconductor element will be bonded may be coated with a material such as an OSP (i.e., organic solderability preservative). This material should be removed before the solder interconnection is formed. Removal of this OSP material is one of the functions of a flux material. Typically, the flux material is applied to the contact surface of a die and the removal of the OSP is accomplished after the conductive structures of the die and the substrate have been brought into contact with one another.
The process of removing the material is time consuming, as it requires a separate fluxing process, and time for the material to be removed (e.g., dissolved, burned off, etc.)
Thus, it would be desirable to provide improved systems and methods providing interconnection of devices in flip chip and related applications.